Loading dock shelters are used around doorways and openings in walls of buildings to protect the building structure from impact with a truck body and to seal the space between the truck body and the building during the loading and unloading of the contents of the truck. Also, the passage of air between the interior of the building and the outside in airconditioned or refrigerated buildings results in substantial increases in energy cost in heating and/or cooling the interior of the building.
In the past, loading dock structures have typically included a flexible head curtain or panel supported along its top edges and positioned to extend across the upper portion of a doorway or opening to sealably engage with the top of a truck body. Two side curtains or panels typically extend inwardly towards each other, downwardly from the sides of the doorway and upwardly behind the head panel to provide sealed engagement with the back of the truck body.
In such installations, the head panel, secured along its top edges, is free to flap unrestrained in the wind. The repeated flexing and snapping of the head curtain produces considerable wear and strain along the edges secured to the underlying support structure and the support ribs sewn into the material. The resultant stress and wear upon the head curtain and side panels requires their continued replacement. Also, when the head panel is permitted to flap unrestrained, the effectiveness of the seal with the truck body is greatly reduced.